The best video on mouse cursors I've seen, by Posy: https://www.youtube.com/watch?v=YThelfB2fvg

It doesn't exactly answer the question, but I -- someone who doesn't watch video and wants text, articles -- have watched this video twice over. It's worth it :)

In fact, I'll post on HN, it's so good. https://news.ycombinator.com/item?id=48108704